sys_ppu_thread: Fix warning

Author: elad335

rpcs3/Emu/Cell/lv2/sys_ppu_thread.cpp

@@ -508,7 +508,7 @@ error_code _sys_ppu_thread_create(ppu_thread& ppu, vm::ptr<u64> thread_id, vm::p
 		return {CELL_ENOMEM, dct.size - dct.used};
 	}
 
-	const vm::addr_t stack_base{vm::alloc(stack_size, vm::stack, 4096)};
+	const vm::addr_t stack_base{vm::alloc(static_cast<u32>(stack_size), vm::stack, 4096)};
 
 	if (!stack_base)
 	{
@@ -533,7 +533,7 @@ error_code _sys_ppu_thread_create(ppu_thread& ppu, vm::ptr<u64> thread_id, vm::p
 	{
 		ppu_thread_params p;
 		p.stack_addr = stack_base;
-		p.stack_size = stack_size;
+		p.stack_size = static_cast<u32>(stack_size);
 		p.tls_addr = tls;
 		p.entry = entry;
 		p.arg0 = arg;